US3411464A - Vertically moving cantilever platform - Google Patents

Description

Nov. 19, 1968 R. H. M KAY VERTICALLY MOVING CANTILEVER PLATFORM 3 Sheets-Sheet 1 Filed June 16, 1966 I NVENTOR. Robert H. MacKay 3 Sheets-Sheet Nov. 19, 1968 R. H. M KAY VERTICALLY MOVING CANTILEVER PLATFORM Filed June 16. 1966 INVENTOR. Robert H. MacKay BY M M ATTORNE S R. H. M KAY Nov. 19, 1968 VERTICALLY MOVING CANTILEVER PLATFORM 3 Sheets-Sheet 5 Filed June 16, 1966 a WEE?" INVENTOR. Robert H. MacKay ATTORNEYS United States Patent 3,411,464 VERTICALLY MOVING CANTILEVER PLATFORM Robert H. MacKay, Fort Wayne, Ind., assignor to Lincoln Manufacturing Company, Fort Wayne, Ind., a corporation of Indiana Filed June 16, 1966, Ser. No. 558,020 7 Claims. (Cl. 108-136) ABSTRACT OF THE DISCLOSURE A vertically movable platform is supported by flexible cables wound about a roller that is positioned at a fixed location above the platform. The roller is spring loaded so that dishes on the platform remain at a fixed level.

My invention relates to a vertically moving cantilever platform, and particularly to such a platform for dining apparatus or utinsels.

Dining apparatus or utensils, such as trays or racks of glasses, are frequently stacked vertically to make the most efiicient utilization of available floor space. Previously, users of such stacked apparatus or utensils had to take a piece of the apparatus or a utensil from the stack at whatever height the next available piece happened to be. The next available piece might be inconveniently high or low. In addition, used pieces of apparatus or used utensils had to be stacked elsewhere or at some distance from the stack of clean apparatus or utensils. Such additional stacking required additional floor space.

Accordingly, an object of my invention is to provide an improved, vertically moving platform for supporting dining apparatus or utensils, the platform moving upward as pieces of apparatus or as utensils are removed so that the top utensil or piece of apparatus remains at substantially the same predetermined height.

Another object of my invention is to provide an improved platform that supports a stack of din-ing apparatus or equipment, and that moves vertically upward as such apparatus or equipment is removed to provide additional storage space beneath the platform for used apparatus or equipment.

Another object of my invention is to provide an improved, vertically' moving platform that comprises a spring for actuating the platform upwardly, the spring being tensioned by the apparatus or equipment placed on the platform, and the spring raising the platform as pieces of apparatus or equipment are removed.

Prior art devices for stacking dining apparatus or equipment were accessible only from the top. In addition, cleaning of these prior art devices was difiicult. These devices were inconvenient in that the stacked apparatus or equipment was not freely accessible. Also, these devices did not utilize the available space to the best advantage. And finally, these prior are devices were relatively ditficult to clean.

Accordingly, another object of my invention is to provide an improved, vertically moving cantilever platform on which dining apparatus or equipment can be stacked in a more accessible manner.

Another object of my invention is to provide an improved vertically moving platform that is relatively easy to clean and that is for use in dining establishments or kitchens.

Another object of my invention is to provide a platform vertically actuated by a sealed spring assembly, the platform being for dining apparatus or equipment and being easily cleaned or sterilized with hot liquids and strong cleansers without special protection or disassembly.

Briefly, these and other objects are achieved in accordance with my invention by a structure comprising a base which may be either movable or stationary. First and second vertical guides are fastened to the base and extend upward in parallel directions from the base. A rolling or moving bearing structure is mounted on each of the guides and arranged so as to slide up and down its respective guide with substantially no transverse or canting. A horizontally extending arm is fastened to each guide, and a platform is fastened to both arms to support the dining apparatus or equipment. The platform causes the arms and the bearing structures to move as a unit. A roller mechanism is rotatably mounted on the base or the vertical guides, preferably at the top of the vertical guides. This roller mechanism contains a torsion spring which is tensioned or wound to cause the roller mechanism to rotate in one direction. The roller mechanism includes one or more flexible cables fastened at one end and wound about the roller. The other end is connected to the unit comprising the platform, the arms, and the bearing structures. The platform tends to maintain the top of the dining apparatus or utensils stacked on the platform at a given height.

The subject matter which I regard as my invention is particularly pointed out and distinctly claimed in the claims. The structure and operation of my invention, together with further objects and advantages, may be better understood from the following description given in connection with the accompanying drawing, in which:

FIGURE 1 shows a side elevation view, partly in cross section, of a cantilever platform in accordance with my invention;

FIGURE 2 shows a plan view of the cantilever platform of FIGURE 1;

FIGURE 3 shows a cross sectional view taken along the lines 33 of FIGURE 1;

FIGURE 4 shows a view, partly in cross section, of the spring and roller mechanism for the platform;

FIGURE 5 shows an end view of the spring and roller mechanism of FIGURE 4; and

FIGURES 6 and 7 show elevation and cross sectional views respectively of a modification of the cantilever platform in accordance with my invention.

The cantilever platform shown in the various figures has been assumed to be used for trays or racks of glasses. However, it is to be understood that the platform may be shaped or designed to hold any particular type of dining apparatus or utensils. As shown in FIGURE 1, the platform in accordance with my invention comprises a horizontal base 10 which may be stationary, or which may be mounted on wheels or rollers 11 'as shown. A pair of vertical guides 13, 14 are attached to the base 10 at spaced locations, and extend vertically upward in parallel directions. In FIGURE 1, only one vertical guide 13 is visible, but FIGURE 2 shows the location of both vertical guides 13, 14. Each of the vertical guides 13, 14 is supported by or fastened to respective sides 15, 16 by horizontal support brackets 17, 18. The structure may be provided with a suitable back 19 (with a handle), a front 20 (with suitable slits or openings), and a top 21 which provide additional strength and also seal the structure to some extent. The structure as thus far described may be assembled in any convenient fashion, as by welding or riveting.

The two vertical guides (FIGURE 3 shows the vertical guide 13) are substantially identical, and each comprises an intermediate section which is formed or bent so that it has a channel or groove 24 at one end of the intermediate section, and a channel or groove 25 at the other end of the intermediate section. These channels 24, 25 face each other and serve as tracks or guides for a set of four rollers 27, 28, 29, 30 which are fastened to respective and similar support arms 31, 32. The support arm 31 runs up and down on its respective rollers in the channels of the vertical support 13, and the support arm 32 runs up and down on its respective rollers in the channels of the vertical support 14. Thus, the two support arms 31, 32 are supported for vertical movement in or by their respective vertical supports 13, 14. The support arms 31, 32 are preferably symmetrical, and extend outward in the direction from the structure, as shown in FIGURE 1. A suitable platform 33 is attached to the two support arms 31, 32 so that the support arms 31, 32 and the platform 33 move as a unit. With respect to FIGURE 1, it will be noted that the support arms 31, 32 and the platform 33 are supported in cantilever fashion. Actually only the two rollers 27, are needed to provide this cantilever support. However, it has been found that the two added rollers 28, 29 provide further guidance and tend to eliminate binding or reduce friction.

As shown in FIGURES 1 and 2, the unit comprising the support arms 31, 32 and the platform 33, is supported by a pair of flexible wires or cables 35, 36 which are respectively attached to the support arms 31, 32. These wires or cables extend upward from the support arms 31, 32 and are similarly wound a number of times around respective sleeves 39, 40 and then securely attached to these sleeves by screws or other fastening elements. The sleeves 39, 40 are supported on a roller tube 42. The roller tube 42 is mounted, as will be described, for rotation in suitable tube brackets 43, 44 which are respectively fastened to the sides 15, 16.

FIGURE 4 shows details of the construction of the roller tube 42 and its internal elements. The sleeves 39, 40 are securely fastened to and rotate with the roller tube 42. The rollerv tube 42 is a hollow, cylindrical metallic structure which is supported at its two ends by ball bearing structures 45, 46. These ball bearing structures 45, 46 are supported on a shaft 48 so that the roller tube 42 is free to rotate with respect to the shaft 48. A helical spring 49, preferably wound of rectangular Wire, is positioned around and extends for substantially the full length of the shaft 48. The left end of the spring 49 is mounted for rotation with the roller tube 42 by a spring roller hub 52. This spring roller hub 52 is positioned inside and is fastened to the left end of the roller tube 42 by any suitable means such as the machine screw shown in FIGURE 4. The spring roller hub 52 has an internal bore or hole which permits this hub 52 to rotate freely on the shaft 48. The left end 50 of the spring 49 is attached to the hub 52 by any suitable means, such as by a force or press fit which, in connection with the pitch or direction of rotation of the spring 49, causes the end 50 of the spring 49 to grip the spring roller hub 52 more tightly as the spring 49 is tensioned. The right end 51 of the spring 49 is fastened to the shaft 48 by a spring shaft hub 53. This hub 53 is securely fastened to the shaft 48, and the right end 51 of the spring is attached to the hub 53 in any suitable manner, such as by the force or press fit provided at its left end 50. Thus the structure shown in FIGURE 4 supports the roller tube 42 for rotation relative to the shaft 48. As the roller tube 42 rotates, it rotates the left end 50 of the spring 49. The right end 51 of the spring 49 is fastened securely to the shaft 48. The shaft 48 is, in turn, secured against rotation by a shaped or keyed end 55 which, as shown in FIGURE 5, has flat, parallel edges which fit into a correspondingly shaped groove or notch 56 in the tube bracket 44, as shown in FIGURE 2. The other end of the shaft 48 is inserted in a hole in the tube bracket 43, and supported thereby.

With the cables 35, 36 wrapped in the proper direction around their respective sleeves 39, 40, as the platform 33 is moved downward, this causes the roller tube 42 to rotate. As the roller tube 42 rotates, it transmits this rotational motion through the spring roller hub 52 to the left end 50 of the spring 49 so as to wind or tension the spring 49 more tightly. It will be recalled that the right end 51 of the spring 49 is tilted to the shaft 48, and the shaft 48 is prevented from rotating by its keyed end 55. Thus, downward motion of the platform 33 causes the sprin 49 to wind up more tightly or to have more tension. Conversely, as the platform 33 moves upward, the tension in the spring 49 is reduced. Or, expressed in another manner, if the weight on the platform 33 is reduced, the tension in the spring 49 turns the roller tube 42 to wind the cables and move the platform 33 upward. It will thus be seen that the structure provides means which permit the platform 33 to move downward when weight is applied or added thereto. This downward movement places increased tension on the spring 49 until the tension on the spring 49 and the added weight reach a point of equilibrium. As weight is removed from the platform 33, the tension on the spring 49 causes the platform 33 to move upward until the tension on the spring 49 and the reduced weight reach a new point of equilibrium. Because of the relatively long length of the spring 49, it has been found that its force is linear over a substantially wide range of applied forces or tensions. Thus, if the platform 33 is adjusted for a predetermined stack of dining apparatus such as trays, the removal of each tray from the stack will permit the spring 49 to provide a slight upward motion of the platform 33 so that the topmost tray on the stack remains at substantially the same height. The tension on the spring 49 may be adjusted by removing the keyed or shaped end 55 of the shaft 48 from its notch 56; turning the shaft 48 in either direction by a wrench or similar tool to provide the desired tension; holding the shaft position by the wrench or tool; and inserting the keyed or shaped end 55 of the shaft 48 back into its notch 56. FIGURE 1 shows an upper position of the platform and support arms in phantom lines.

FIGURES 6 and 7 show another embodiment of my invention, FIGURE 7 being taken along the lines 77 in FIGURE 6. In this embodiment, the vertical guides 13, 14 shown in the previous figures have been replaced by a pair of vertical tubes 60 which serve as supports for two support arms 61. The support arms 61 are mounted for movement along the vertical tubes 60 by sleeve or roller bearings 62 which fit around the outside of the vertical tubes 60 as shown in FIGURE 7. It is preferable that upper and lower sleeve bearings 62 be provided in order to provide proper cantilever support. Also an additional sleeve hearing may be provided if desired. The other structure for the tray platform is otherwise the same as that shown in FIGURES 1 through 5.

It will thus be seen that my invention provides a new and improved, vertically moving, cantilever supported platform. This platform is accessible from a plurality of directions, and can be easily cleaned. The main moving or motivating element, namely the torsion spring, may be sealed within the roller tube so as to protect it against water and cleansers. The relatively long length of this spring provides a relatively wide range of weight or forces which can be accommodated on the platform. Persons skilled in the art will appreciate that modifications may be made to my invention. For example, other cantilever support structures may be provided. The roller tube may have only one sleeve with a cable for moving the platform, or the roller tube may be provided with more sleeves and cables for moving the platform. And, the roller tube may be positioned at other locations (such as on the base) if the cables can be threaded through pulleys to the proper locations. The roller tube may also be positioned on the vertical guides. Therefore, while my invention has been described with reference to a particular embodiment, it is to be understood that modifications may be made without departing from the spirit of my invention or from the scope of the claims.

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A platform for movement up and down, comprising:

(a) a base;

(b) first and second vertical guides fastened to said base, said guides being spaced from each other and extending vertically upward from said base;

(c) first bearing means mounted on said first guide and arranged to slide up and down on said first guide; (d) second bearing means mounted on said second guide and arranged to slide up and down on said second guide;

(e) horizontal platform means fastened to said first and second bearing means, said first and second bearing means and said horizontal platform means being movable as a unit up and down along said first and second guides;

(f) a roller mechanism rotatably mounted in a fixed location with respect to said first and second guides, said roller mechanism having rotational biasing means associated therewith that tend to rotate said roller mechanism in a predetermined direction;

(g) and flexible means connected at one end to said roller mechanism and extending vertically downward therefrom, the other end of said flexible means being connected to said unit of said horizontal platform means and said bearing means for moving said unit upward in response to the force of said biasing means exceeding the weight on said platform, and for moving said unit downward in response to the force on said unit that exceeds the forcing of said rotational biasing means.

2. A cantilever platform for dining apparatus and utensils or the like, comprising:

(a) a base;

(b) first and second elongated support elements each having one end fastened to said base, said support elements each extending vertically upward in the same parallel direction from said base;

(c) first and second movable elements positioned on said first and second support elements respectively for movement along said support elements in substantially only a direction parallel thereto;

(d) a platform fastened to and supported in cantilever fashion by said first and second movable elements for keeping said first and second movable elements at substantially the same distance from said base and for moving with said first and second movable elements as a unit;

(e) a rotatable element mounted at a fixed location on said support elements near the top thereof;

(f) Spring bias means having one end fixed and the other end connected to said rotatable element;

(g) and means comprising at least one fiexible member having one end wrapped around and attached to said rotatable element, extending vertically downward from said rotatable element, and having the other end attached to said unit for increasing the tension on said spring bias means in response to increased downward force applied to said unit, and for causing said unit to move upward in response to decreased downward force applied to said unit.

3. The cantilever platform of claim 2 wherein said spring bias means comprises a helical spring wound about a shaft, said spring and shaft being positioned Within said rotatable element.

4. The cantilever platform of claim 3 wherein said one end of said helical spring is fastened to one end of said shaft, and said other end of said helical spring is fastened to said rotatable element at the end thereof away from said one end of said shaft.

5. The cantilever platform of claim 2 wherein said first and second support elements each comprise a pair of spaced vertical channels facing each other, and wherein said first and second movable elements each comprise a set of rollers respectively mounted in said channels to permit vertical motion of said movable elements and to support said unit in cantilever fashion.

6. The cantilever platform of claim 2 wherein said first and second support elements each comprise a tubular structure, and wherein said first and second movable elements each comprise an elongated sleeve bearing positioned around said tubular structure to permit vertical motion of said movable elements and the support said unit in cantilever fashion.

7. The cantilever platform of claim 3 and further comprising first and second sleeves mounted on said rotatable elements, and first and second cables wrapped around and attached to said sleeve at one end and attached to said unit at the other end.

References Cited UNITED STATES PATENTS 1,359,399 11/1920 Lewis 108-147 3,123,023 3/1964 Bronson 108-136 3,123,024 3/1964 Bronson 108136 3,123,829 3/1964 Bronson 108136 3,154,029 10/1964 Bronson 108-436 JAMES T. MCCALL, Primary Examiner.

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